• The Journal of Advanced Prosthodontics
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• v.9 no.4
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• pp.315-320
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• 2017

PURPOSE. The aim of this investigation was to analyze the dimensions of clinical crowns and to classify the crown and the gingival type in the anterior teeth in Korean young adults. MATERIALS AND METHODS. Casts were obtained from 50 subjects ranging in age from 24 to 32. Measurements of length and width were made on the casts using a pair of digital calipers on the entire dentition. Crown thickness and papilla height were also measured and MDW/CL (mesiodistal width to clinical length) and CW/CL (cervical width to clinical length) ratios of the maxillary anterior teeth were calculated. The K-clustering method was used for CW/CL to classify the anterior tooth shape into three groups (tapered, ovoid, and square), and one-way analysis of variance and Duncan's post-hoc comparison were used to evaluate statistical significance between the groups. Pearson's correlation analysis was performed between tooth shape and papillary height (PH) to demonstrate the correlation between tooth shape and gingival morphological characteristics. RESULTS. The average length of the maxillary central incisors was 9.89 mm; the mesio-distal width was 8.54 mm; and the ratio of width/length was 0.86 in Korean young adults. The average bucco-palatal thickness of the central incisor was 3.14 mm at the incisal 1/3 aspect. Ovoid type was the most common tooth shape (48%), followed by square type (29%) and taper type (23%) in the central incisors of Korean young adults. Tooth shape and gingival type were correlated with each other. CONCLUSION. New reference data were established for tooth size in Korean young adults and the data show several patterns of tooth shape and gingival type. Clinicians should diagnose and treat based on these characteristics for better results in the Korean population.

• Korean Journal of Environmental Biology
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• v.35 no.1
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• pp.64-82
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• 2017

Two species of the minuta-subgroup within the oncaeid copepod genus Triconia $B{\ddot{o}}ttger$-Schnack, 1999 collected in the equatorial Pacific Ocean are newly recorded. A female T. minuta (Giesbrecht, 1893 ["1892"]) and both male and female T. umerus ($B{\ddot{o}}ttger$-Schnack and Boxshall, 1990) from the northeast equatorial Pacific are redescribed with the comparison of its morphological details, which differs from previous studies, in terms of the larger body size, the length to width ratio of the genital double-somite, the relative length of the outer basal seta on P5, and the ornamentation of the appendages. The characters, which are used for identification, such as the length ratio of the outer subdistal and outer spine versus the distal spine on P3-P4, and the outer spine length of the middle exopodal segment on P3 and P4 are reported for the first time. Information on the variations in the endopodal spine lengths of swimming legs 2-4 is also provided for T. minuta and T. umerus, with the summary of the wide zoogeographical distribution of these two species.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.19-28
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• 2004

Tooth is the most important element in esthetic consideration on facial area. Tooth alignment which is in harmony with gingiva, lips, and face is also key element. The purpose of this study was to give a clinical discipline for restoration of gingival contour, which contains a ratio of maxillary 6 anterior teeth, research for gingival contour etc., in case of rehabilitation of maxillary anterior teeth. 300 Dankook university dental school students ,who is their twenties and free from periodontitis, participate in this study. The result was from each 70 males and females who had normal occlusion and tooth alignment. Length, width and length/width ratio of maxillary 6 anterior teeth were 0.74-0.81 in male, 0.81-0.84 in female. There was significant difference between male and female. The most deepest position of gingiva in maxillary central incisor and canine was located in distal part of teeth and maxillary lateral incisor was middle portion. In maxillary central incisors, gingival line of the most deepest point appeared significant difference between male and female (p<0.01) whereas there was no difference in lateral incisors and canines. Distance between interdental papilla apex and the most deepest portion appeared significant difference between male and female. Distance of the deepest position of gingiva is statistically significant except maxillary central incisors and lateral incisors. Standard deviation and mean of the width of labio-lingual were measured in cervical area and there was a significant difference both male and female.(p<0.01) From this result, we could get the mean of maxillary anterior gingival line and these results have great value in clinical guidance in studying maxillary anterior teeth.

• The Korean Journal of Mycology
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• v.20 no.4
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• pp.309-314
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• 1992

Nine species of powdery mildew fungi were examined to understand the change in size of conidia in relation to air temperature. Of these, Sphaerotheca aphanis, S. fusca and S. pannosa showed constant value of conidial sizes regardless of changes in air temperature. The length/width ratio in the conidia of Erysiphe, artemisiae and E. sordida increased as the air temperature rose. E. cichoracearum gave the result against that shown in the above two species of Erysiphe. The conidia of Microsphaera pseudolonicerae became decreased in their width as the air temperature fell. The length/width ratio of conidia was markedly increased. M. alphitoides and M. robiniae showed variable size measurements in conidia regardless of changes in air temperature and studies for it needed for additional examination in future.

• Journal of Advanced Navigation Technology
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• v.26 no.5
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• pp.344-349
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• 2022

A compact LPDA antenna consisting of right triangle-shaped dipole elements appended with strips is proposed for UWB applications. First, right triangle-shaped dipole elements are used instead of conventional strip dipole elements to reduce the width of the LPDA antenna. Second, the spacing between the LPDA elements is decreased to reduce the length of the LPDA antenna. Finally, strips are appended at the ends of the right triangle-shaped dipole elements in order to further reduce the width of the antenna. A prototype of the proposed antenna with 16 elements and gain > 4 dBi is fabricated on an FR4 substrate with dimensions of 44 mm×30 mm. Measured frequency band of the fabricated antenna is 2.99-14.76 GHz for a VSWR < 2, which ensures UWB operation, and measured gain range is 4.0-5.5 dBi with a front-to-back ratio larger than 10 dB. The length and width of the proposed compact LPDA antenna are reduced by 40.9% and 20.6%, respectively, compared to the conventional LPDA.

• Journal of Mechanical Science and Technology
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• v.14 no.3
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• pp.314-319
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• 2000

Back-face strain compliance (BFS compliance) for the four-point bend specimen has been calibrated for various crack length ratios. Finite element technique was employed to simulate four-point loading and calculate back-face strain of the bend specimen. The numerically determined strain variation along the back face indicates that the sensitivity to gage placement increases with crack length and back-face strain at the gage length less than O.2W, where W is the width of the bend specimen, can be measured within 5% deviation of the maximum BFS. Non-dimensional back-face strain compliance, -E'BCW, was calibrated with FE analysis and experiment. The experimentally determined compliance indicates good agreement with the numerical compliance and can be expressed as a function of crack length ratio.

• Journal of ILASS-Korea
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• v.7 no.1
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• pp.29-35
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• 2002

This study describes the external spray characteristics of deflector nozzle such as the breakup procedures of liquid sheet, spray angle, breakup length and bubble behaviors of spray at deflector nozzle. In order to visualize the spray behaviors shadow graphy technique were used. According to the increase injection pressure, deveopment of the spray passes through the dribbling, distoted jet, closed bubble due to the contraction by form a conical sheet like as the simplex swirl atomizer. As trying the analysis of the ratio of bubble length and width it was found that the ratios is comparable. Spray cone angle was nearly $90^{\circ}$.

• Computers and Concrete
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• v.22 no.2
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• pp.221-225
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• 2018

In this paper, vibration analysis of concrete foundations resting on soil medium is studied. The soil medium is simulated by Winkler model considering spring element. The concrete foundation is modeled by thick plate elements based on classical plate theory (CPT). Utilizing energy method consists of potential energy, kinetic energy and external works in conjunction with Hamilton's principle, the motion equations are derived. Assuming the simply supported boundary condition for the concrete foundation, the Navier method is used for calculating the frequency of the structure. The effect of different parameters such as soil medium, mode numbers, length to width ratio and length to thickness ratio of the concrete foundation are shown on the frequency of the structure. At the first, the results are validated with other published works in order to show the accuracy of the obtained results. The results show that considering the soil medium, the frequency of the structure increases significantly.

• Journal of Environmental Science International
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• v.30 no.9
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• pp.709-717
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• 2021

This study evaluated the growth, physiological responses and productivity based on the intercropping ratio of cherry tomato (Lycopersicon esculentum L.) with basil (Ocimum basilicum L.). on the rooftops to determine out the efficient ratio in urban agriculture. From April to September 2019, an experiment was conducted on the rooftop of Konkuk University Glocal Campus. Cherry tomato and basil were selected as companion plants for eco-friendly urban agriculture on the rooftops. Each plot was created with a width of 100 cm, length of 100 cm, and height of 25 cm. After installing drainage and waterproof layers from bottom to top, substrate was laid out with a height of 20 cm. Intercropping ratio was consisted of a single tomato plant (TC), 2:1 tomato to basil (T₂B₁), 1:1 tomato to basil (T₁B₁), 1:2 tomato to basil 2 (T₁B₂), and a single basil plant (BC), were conducted using a randomized complete plot design with five treatments and three replication (a total 15 plots). Measurements were divided into growth, physiological responses, and productivity parameters, and detailed items were investigated and analyzed by classifying them into plant height, leaf length, leaf width, number of leaves, root length, root collar caliper, chlorophyll contents, fresh weight, dry weight, number of fruit, fruit caliper, fruit weight, and sugar content. Comparative analyses of cherry tomato with basil plants by intercropping ratio, growth, physiological, and productivity responses are determined to be efficient when the ratio of cherry tomato to basil ratio is 2:1 or 1:1.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.3
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• pp.50-57
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• 2014

In this study, we investigated the physical properties of kraft pulps made from rice husk, peanut husk and garlic stems. These agricultural byproducts were collected individually, and then various pulps were manufactured from them by controlling active alkali, sulfidity, reaction time and the liquor ratio in the kraft pulping process in order to analyze the applicability of these agricultural byproducts as raw materials for kraft pulps. After kraft pulping, we measured yield, flake content, fiber length, fiber width and freeness of pulps, and the fiber shapes of the pulps were observed by using an optical microscope. When the higher active alkali, longer reaction time and lower liquor ratio were applied in kraft pulping process, reject content decreased and fiber yield increased. The pulp from garlic stems had the longest fiber length and that from rice husk showed the highest intial freeness. All of the pulps from agricultural byproducts showed higher initial freeness, shorter fiber length and the similar fiber width compared to OCC, BCTMP and hardwood BKP. The fibers of the pulps made from agricultural byproducts showed a similar shape to those of commercial pulps. It was concluded that these agricultural byproducts had a potential as raw materials to produce an alternative pulp to the commercial pulps.